2-methyl-4-keto-3-substituted thiazolinium dye intermediates



Patented July 1 7, 1 951 UNITED STATE s PATENT OFFICE 2,561,2452-METHYL-4-KETO-3 SUBSTITUTED THI- AZOLINIUM DYE INTERMEDIATES Thomas R.Thompson and Stanley P. Popeck, ssignors to General Aniline New York, N.Y., a corpo- Binghamton, N. Y., a & Film Corporation,

ration of Delaware No Drawing. Application December 30, 1949, Serial No.136,150

10 Claims.

' hereinafter.

The foregoing objects are accomplished, in accordance with the presentinvention, by condensing an c-halogen acetic acid or an a-halogenpropionic acid with N-mono-substituted thioacetamide. The condensationreaction is best effected by simply allowing the coreactants to stand attemperatures ranging from C. to 40 C., and preferably at about roomtemperature in an inert solvent, such as acetone. After several hours,the product separates as crystals. Ordinarily, an excess of thea-halogen acetic acid is used, and it is most convenient to employ equalweights. In cases where the product does not separate from the reactionmedium, it may be necessary to effect precipitation by adding ether,benzene, petroleum ether, and the like.

The thiazolinium salts obtained by the foregoing procedure arecharacterized by the following general formula:

11 RO--S O= (BCHB R( X wherein R represents hydrogen or a methyl group,R1 represents an alkyl, cycloalkyl, aryl, aralkyl or heterocyclic group,e. g., methyl, ethyl, propyl, butyl, etc., cyclopentyl, cyclohexyl,etc., phenyl, naphthyl, o-,'m-, and p-tolyl, 0-, m-, andp-methoxyphenyl, benzyl, phenethyl, etc., thienyl, pyrryl, furyl, andthe like, and X represents a halogen, e. g., bromide, chloride, or

iodide.

The reaction involved, while utilizing an ahalogen acetic acid or ana-halogen propionic acid, is believed to take place as follows:

wherein R, R1 and X have the values given above.

As typical examples of thioacetamides, the followingN-methylthioacetamide N-ethylthioacetamide N-propylthioacetamideN-isopropylthioacetamide N-butylthioacetamide Thioacetanilide2-thioacetnaphthalide o-Thioacetotoluide m-Thioacetotaluidep-Thioacetotoluide o-Thioacetaniside p-'IhioacetanisideThioacet-asymm-m-Xylidide 2-thioacetaminothiophene The following areexamples of a-halogen acetic and a-halogen propionic acids:

N-mono -substituted may be mentioned:

a-Chloroacetic acid a-Bromoacetic acid c-IOdOLCBtlC acida-Chloropropionic acid a-Bromopropionic acid a-Iodopropionic acid Thefollowing examples describe the preparation of some of the2-methyl-4-keto-3-substituted-thiazolinium halides.

, Example I HzC--S 0: 41-6113 4) OH: 2-methyl-3- (p-methoxyphenyl)-4-ketothiazolinium bromide A solution of 5 grams of p-thioacetanisidein 25 cc. of acetone was added to a solution of 5 grams of bromoaceticacid in 25 cc. of acetone and the resulting mixture allowed to stand at25 C. for 1 /2 hours. The reaction product separates as crystals and waspurified by washing with acetone and finally with ether. A yield of 7.5grams of a product melting at 142 C. with decomposition was obtained.

' a I U/Eg 2-methyl-3- (Z-thienyl) -4-ketothiazolinium bromide ExampleIII H2C S o=c CH3 2-methyl-3-pheny1-4-ketothlazoliniun1 bromide Amixture of 2 grams of bromoacetic acid and 2 grams of thioacetanilidedissolved in cc. of acetone were allowed to stand at room temperature(about C.) for 2 hours. The product separates in crystalline form andwas purified by washing with acetone and finally with ether. A yield of2 grams of a product melting at 144 C. with decomposition was obtained.

Example IV C l-CH 2-methyl-3- Z-naphthyl) -4-ketothj.a z o lin iurn,bromide.

A solution of 5 grams of 2-thioacetnaphthalide in 25 cc. of acetone wasmixed with 5 grams of bmmcaqe ic ac d 2. ce- .o c on d. he elene mixt reall wed to sta t oo e n perature for 2 hours. The. product separatescrystalline form and was purified by washing with acetone and finallywith ether. A yield of 4.7 grams of a product melting. at 195 C. withdecomposition was obtained.

Example V Example I was repeated with the exception that 3.4 grams ofchloroacetic acid was used in place of 5 grams of bromoacetic acid. The2-methy1- 3- (p-methoxyphenyl) -4-ketothiazolinium chloride was thusobtained.

In addition to the above described salts, which have a reactive methylgroup in the 2-position en ersaQ iv-e m tb en ze e the-pcs t en. .-fi 2ln um dye s lt. term i e 9 2: e a m thy e ou l bot e s-Poet t 5 17% h metre by ;.o.n ens ;ne a ah -19: 10 I sai acid with? any. one of the rm:iliilli fi l Nrmn bwta ed, h c tem dee Th fi com unds rsu f l a n e medates 91. he P e at n. oi d amete ya i y s The condensatio n an. whaes-en w a l t a id. with a thiopropanilide leads to a heterocyclic saltcontaining an ethyl-groupinthe 2-position. The compounds, however,possessing the two reactive groups, i. e., a reactivemethylin the2-position and a reactive methylene in the 5-position are most usefulfor the synthesis of trinuclear dyes.

The above dye salts may be converted to salts other than halogen bytreating the halogen salt with an aqueous or aqueous alcoholic solution7 4 containing a sodium or potassium salt of perchloric orthiocyanicacid.

The foregoing 4-ketothiazolinium dye salt intermediates may be employedin the synthesis or trinuclear cyanine dyestuffs as sensitizers forsilyer halide emulsions. For example, by condensing 1 molecularproportion of a 4-ketothiazolinium salt with 2 molecular proportions ofa cyanine dyestuff intermediate such as Z-methylmercaptobengothiaz olemethiodide in a medium of pyridine, triethylamine, and acetic anhydride,there is produced a trinuclear cyanine dye.

While there have been pointed out certain preferred embodiments of theinvention, the same is not limited to the foregoing examples,illustrations, or to the specific details given therein, but is capableof variation and modifications as to the reactants, proportionsandconditions employed.

We claim:

1. A l-keto-3-substituted thiazolinium salt characterized by thefollowing general formula:

wherein R represents a member selected from the class consisting ofhydrogen and methyl group, R1 represents a member selected from theclass consisting of lower alkyl, lower cycloalkyl, aryl of the benzeneand naphthalene series, aralkyl of the benzene series, and 5-memberedheterocyclic radical containing a single hetero atom inv the ring andhaving a nuclear carbon atom joined to the nitrogen atom of thethiazolinium nucleus, and X represents a halogen.

2. A e-ketothiazolinium cyanine dye. interme-. diate hayin the followingformula:

4. A 4- ketothiazolinium cyanine dye interme;

diate arms, he g lew ne form la:

5. A 4-ketothiazolinium cyanine dye intermediate having the followingformula:

6. A process for the production of 4-keto-3- substituted thiazoliniumsalts which comprises reacting at temperatures ranging from 0 C. to 40C., a compound of the general formula:

with a compound corresponding to the following formula:

of the benzene and naphthalene series, aralkyl of the benzene series,and 5-membered heterocyclic radical containing a single hetero atom inthe ring and having a nuclear carbon atom joined to the nitrogen atom ofthe thiazolinium nucleus and X represents a halogen.

'7. A process for the production of a 4-ketothiazolinium cyanine dyeintermediate which comprises reacting at about room temperature,thioacetaniside with bromoacetic acid.

8. A process for the production of a 4-ketothiazolinium cyanine dyeintermediate which comprises reacting at about room temperature,2-thioacetaminothiophene with brornoacetic acid.

9. A process for the production of a i-ketothiazolinium cyanine dyeintermediate which comprises reacting at about room temperature,thioacetanilide with bromoacetic acid.

10. A process for the production of a -ketothiazolinium cyanine dyeintermediate which comprises reacting at about room temperature,thioacetnaphthalide with bromoacetic acid.

THOMAS R. THOMPSON. STANLEY P. POPECK.

REFERENCES CITED UNITED STATES PATENTS Name Date Thompson Mar. 22, 1949Number

1. A 4-KETO-3-SUBSTITUTED THIAZOLINIUM SALT CHARACTERIZED BY THEFOLLOWING GENERAL FORMULA: